Manufacture of sulfuric esters of leuco vat dyestuffs



Patented May 9, 1950 MANUFACTURE OF SULFURIC ESTER/S OF LEUCO VAT DYESTUFFS Samuel Coffey, George William Driver, David Alexander Whyte Fairweather, and Francis Irving; Manchester, England, assignors to Imperial' Chemical Industries, Limited, a corpora- "ti'on of Great Britain VNoJDrawing. Application March 25, 1947, Serial .No. 737,106. In-.Great Britain March 26, 1946 6 Claims. .1 y 1 Thi invention relates'tothe manufacture ,of dyestuffs and intermediates arid in particular to the manufacture of the sulphuric esters of leuco derivatives of vat dyestuffs and dyestuff intermediates and the salts thereof.

The production of ester derivatives of *vat dyestufis for the direct dyeing or printing "of fabrics'is well-knownand processes have been described for the i manufacture of these ester derivatives directly from the Wat dyestuff by treating the vat dyestufi in suspension. in .a tertiarybase in thejpresen ce of a metal with sulphur'trioxide or a substance.which cansive rise to sulphur"trioxide'in the reactionmixture such as for example an alkyl sulphuric acid halide or non-alkylated sulphuric acid chloride or a salt thereof or"fuming .sulphuricacidor a salt of pyrosulphuric. acid or withpyrosul-phuryl chloride. Processes have also been..described in which these reactionsarecarried .outrinlthe presence of diluents, preferably diluents such as for example acetone-aridnitrobenzene, which do notreact withthe: esterifying --agent.

It has been proposed tonne-variousztertiary bases such asAor example, vpyridine,.iuuinoline and dimethylaniline in :the :above :freaction but only ,pyridine andccertain :homologues of pyridine have hitherto been widely usedzinthe commercial applications of: the reaction. thermore the use :of :inert' diluents with the pyridine has not been. successfulfinpracticeiand has not been widely i used in commercial" applications of the reaction.

The use of pyridine in the-above reaction has however certain disadvantages. Pyridine itself is expensive and "a comparatively large amount is usuallyrequired'. Furthermore1thefyield'and quality of the leuco sulphuric ester derivative is n'ot satisfactory with "many :vat dyestufis. Also it has not'hitherto'been' fouri'd'rposs'ible to convert certain classes of vat vdyestuffs. into their leuco sulphuric .esters'by "the use] of pyridine or other tertiary basesiin the above reaction.

The objects offthisinv'ention are 'to provide a cheaperprocess 'for the .manufactureo'f ester derivatives directly -from vat dyestuifsuandldyestuff intermediates and to provide a process which will be more widely applicable than the processes :hitherto known.-

We have found rthat' improved results 1 are obtained in the i manufacture- .of .1 leucoa sulphuric ester derivatives. of: vat dyestuffs; and dyestuifaintermediates, rand tthe zsalts :thereoflcby using'za modified *process zcharacterisedzzmnthat the -ssu1-- phation: is'zcarried 1 outdnithe presencefoi tan. .or

garlic amide in which the hydrogen atomseatof a .dyestuff or dyestufi" intermediate characterised in that the dyestufi or dyestufi intermediate is treated in the presenceof a metal and an or ganic amide in which the hydrogen atoms attached'to the amide nitrogen atom "have been replaced by hydrocarbonradicles or substituted hydro-carbon radicles, with or without'the addi-- tion of diluents, with sulphur tri'oxide or withi'a substance which cangive rise to sulphur trioxide in the reaction mixture, either alone or in the presence of other substances which may be added if desired.

The. reaction can be applied to anthraquinon'e and its derivatives andto indigo anditsderivatives.

Examples of specific compounds to which the reactionmay be applied are anthraquinone, '2- chloroanthraquinone, 2 chloro-B-acetylaminoanthraquinone, 114- dibenzoylaminoanthraqui none; 1:4 "di (m-methane-sulphony1benzoylamino) -anthraquinone, 16: ll-dimethoxy-dibenzanthrone, 4210- dibromoanthanthrone, d-ibenzpyrenequinone, 1:1':4:1" trianthrimidecarbw zole, tetrabromindigo and thioindigo.

.As examples of suitable amidesfor use'in thereactionthere may be mentioned dimethylformamide, diethylformamide, dimethylacetamide, diethylacetamide, tetramethylurea, formyland acetyl-piperidide. formylmorpholide; tetra-methyladipamide, dimethyl-benzamide, dimethylurethane, N methylacetanilide and N methylphthalimidine. V

The 'diluents which are used may be diluents which have comparatively little effect on the course of the reaction such as for example acetone, methylethylketone, acetonitrile, benzonitrile,'*benzene or nitrobenzene or they may *be dilue'nts which materially modify the reaction conditionsand' the course ofthe reaction. Thus for example it'is' possible to add a tertiary base such as" for example pyridine or triethylamine" and the use of "such a base together with-an amide as hereinbefore defined allows thebasic nature of the reaction mixture" to be varied and control-lediso that the reaction conditions neces sary for forming. sulphuric ester derivatives from a wide range of compounds can be obtained.

Asexamplestof substances which can vgivesrise to sulphurt'rio'xide'inithereaction mixtureithere mayabetmentionedithe addition compound of sulthe following examples in WhichLtheparts are by 7 weight. 7 m

Example 1- a 9.5 parts of sulphur trioxide are added to 24 parts of dimethylformamide withj-co'oling and 1516' p parts of 16:17-dimethoxydibenzanthrone are then added. The mixture is stirred at 20C. and 6.8 parts of finely divided: brass powder (20% zinc) are added. Themixture is then stirred at 20C. for'l hour and poured into a solution of 11 parts fof caustic sodainlSQjpattsf of water.' The suspension is heated"to'50 C2 and the metal residues are removed by filtration."'Thei filtrate is.

then'vaporated to dryness.

In 'placeof'dimethylformaniide used in this example the same quantity of diethylformamide maybe used."

1 Examplez- To' 95011161611 "of dimethylformamide sulphur triojxidemade by reacting 8.6 parts of sulphur:

triox'idewith" 26 parts ofjdimeth'ylformamide,

1 parts of acetone are stirred and cooled ii there are added l5-partsof'tetrabromoindigo and 6 parts ofbrass: 'The mixture'is stirred'for 3 hours jat30 Grand theirpoured-into a solution of l=5tparts of'caustic'sodain '180'parts' of water;

The suspension is filtered and the leuco sulphuric sodium esteris? salted out from. the filtrate with chloride-filtered ofiia'ndidrieda" .Ew .mi lerv v v 10.4 parts -01" methyl-- chlorosulphonate are addedtoa mixture of -30 parts of dimethylformamide and'-'16 parts of :acetonewith cooling. 4.5

parts of l :4-dibenzoylaminoanthraquinone and 1.2 parts 'of finely divided iron powder are added to theresultingsolution at 15 C. The mixture is stirred for 1 hours at 15C. and is then poured into 240 parts of 5% sodium carbonate solution.

Theiron residuesare separated by filtration. The

yellow; colouredfiltrateis extracted with benzene to remove 'dimethylformamide and concentrated sulphuric ester is salted outfromrthe filtrates-v. as

in vacuo." Thesulphuricester'is salted'out, filteredjofiand dried Z v -E i tl fl Y 15.6" parts of methyl chlorosulphbnate .are

added to 'a mixture 0112.5 :parts of dimethyl-.

formamide and 10.5 parts of acetone at l0-15 (3.

The. mixture is heated to-203- C. .and,4.2 parts of finely divided anthraquinoneand 2.4 parts of iron powder are then added. Themixture is stirred for 1 hour at 20 C. and then poured into.200 parts.

of cold watercontaining lfiparts of sodium car-.

' bonate The suspension is filterdjthefiltrate concentratedand the sodium anthrahydroqui none disulphuric esteris salted. out, filtered off I anddried- 6.5 parts of 1:1:4:1"-trianthrimidecarbazole' andpartsof iron powder areadded' to'the mixture at 20 C; in 15 minutes. The mixture is The leucosulphuricfesterisisolated by pouring if stirred at 20 C. for 5 hours and then poured into 230 parts of 10% sodium carbonate solution. The suspension is filtered. and the .dyestufiis. isolated by evaporating t-heqfiltrate under;reduced..pressure.

Example 6 .A mixture of 23 parts of formylpiperidide and 16 parts'of-ac'e'tonitrile is cooled during the addition of 13 parts of methylchlorosulphonate. 4.2 parts of anthraquinone' and 3 parts of iron powder are then added. The reaction mixture is stirred for 1 hour at 15 C. and then poured into 250. parts of water containing 16 parts of sodium carbonate. The metal residues are separated by filtration and the filtrate is distilled in vacuo.

The anthrahydroquinone disulphuric ester is saltedxout from the filtrates in substantially quantitative yield. Instead of acetonitrile theremaybe used :3157 diluent 'b'enzonitril'e, 'acetorfebr *metliylethy1- tong. v ..Ea:ample7 Y The iron powder used in, Example 4 isreplacedi by anequal weight of finely; divided nickelqpowderj and e r ct is a ried. ,O1l12'; E-;f 0 .9l C-Lin do 2 S di m anthr hydroqu noneldi sulphuric ester is obtainedin l igh yields;

I -Exampla8 v tetrarnethyl'a 10.2' parts Io'r additi'onoffi5 parts of?hi'ethylclilorosulphonefte;i. 5.2 parts of indigo and 2.4 partso'f irdh'pev dr f" are then added. The mixture is heatedito 5910" and stirred at this temperatur "roriermnut' the reaction mixture into 2Qqparts of sodiui'nf carbonate" solution, filtering, concentrating v the" d salltii gout filtrates "by: vacuum 1 distillation V 7 Example!) v A mixture QfLZOparts' offdiethylacetamide' an 15 parts of acetorfitrile"is"stirred afid ceeieeuar ing thea'ddition'fif 721 partsbf clilbrosulphldm acid; 3.75 parts of ""4 lo -"dichloroanthanthrdn and 3.2 parts 'ofcoppen'powder" are the A dde Themixture is stirred fOI'T-3 hours'iat rammed. then poured "into 300 parts": of 5 sodium-dear bonate. The metal residues arexseparttedab warmingth'e suspension and filtering: The leuc' a bright yellow crystalline precipitate.

i; V Eard1n"z'7l e1D j Amixture of -15 parts of,dimethylformamide 5 and'9parts ofbenzfene is stirred andaeooledduring the addition of 'Ll parts .of .chlorosulph onic; acid. :6.2 partsof dimethoxydibenzanthron and 3.2 parts of copperpowder are then. added. -'rh mixtureis stirred at.,15 Crier 1.110111. and.-.then.;,. poured .into dilute. sodium,,carbonate .solution, The suspension is vacuums;v distilled; to v r-emeve., n ene and t co centrate...and,is th n e d-m The si e wash d Wi h water e tire; sulphuric ester is .s alte'd out f romg es and'w smniss q 4 I. 1 ;.-'..E ampZefl1- 1.W V I I .10 parts of N-f ormylmorpholide are'addedto; 5 parts" of acetone and 3 parts or ethyiemorq'sm? 7 phonat'e are"theii' ad 'led"th' the cooled mixture. 2.1 parts'of 1:4-di(in -mthansulphonylbenzoyl-'" f amino) i-anthraquinorre" amihza art of iron p6w-.'" der are then addediarid'themixture'is"stirrediat; 15-20? .C'; for: 2*h'ours;"j The leuco: sulphuric wt'ei' lstisolat'edcin :highnyieldcas:ia-iyelliivw crystalline substance byrpourin xthe:reactionumixture ainto 100 parts of .sodium :carbonatepfiltering the snspension'iiand-r:thenuconcentratingrand salting the filtrates.

, Example 712 i *253 parts of-di'meth'ylfonnamide ar stirred and cooled-'during the addition of 751 parts of 'ch1oro-" partsofbopper-powder"are then-added; The -re action -mixture "is *stirred 'at *40'-50 C. for about- 3O minutes-until the red colour has :disappeared:

The f leuco sulphuric ester *is'--isolated by' pouring the a'eaction'mixture-into sodium carbonate solutitin; fiftringthesuspension andsalting out irom' the filtrate by means "of common-salt.

. I I ,Ewamplel3 "E13 parts of N-i'dimethylbenzamide=are dissolved in 24 pairtsfof iacetona and 6.5 parts =of-methyl-" Eaxample 14 UfiAimixture of 16.,partsnf zacetoneaand 5:8,parts o'fitetramethylurea, are, stirredcandsicooled 'Ttluring theuaddition of 6.5 sparts-:ofs-methylchlorosulphonate and then 3 parts of 2-chloro-3-acetylaminoanthraquinone and 1.5 parts of iron powder. Stirring is continued for 1 hours at 35-40 C. and the product is isolated as in the previous example.

Example 15 5.8 parts of chlorosulphonic acid are added slowly with stirring and cooling to parts of tetramethylurea. 3.3 parts of dibenzpyrenequinone and 2.5 parts of copper powder are then added. The mixture is heated to 45 C. and stirred at that temperature for hour. The mixture is then added to a solution of 10 parts of sodium carbonate in 100 parts of water and the suspension so obtained is filtered. The residues are washed with hot water. The leuco sulphuric ester is precipitated from the combined filtrates and washings by the addition of common salt.

Example 16 7.8 parts of methyl chlorosulphonate are added to 10 parts of dimethylurethane and the mixture is heated to 100 C. and stirred at that temperature for 20 minutes. The mixture is cooled to 20 C. 5.2 parts of 16:17 dimethoxydibenzam throne are added and then 3 parts of copper powder, and 12 parts of acetonitrile. The mixture which rapidly turns red in colour is stirred for some hours until all the vat dyestufi is converted to the leuco sulphuric ester. The reaction mixture is poured into dilute sodium carbonate solution, the suspension concentrated and then filtered and the residue washed with Water. The leuco sulphuric ester is then salted out from the combined filtrates and washings.

Example 17 A suspension of 12.2 parts of N-methylacetanilide in 20 parts of acetonitrile is stirred and 5.4

mixture is :then taddedxto ;a.-solution'of-r8 :parts' f sodium .carbonatein 200i partsof wateruw'llhe; suspension ,is;-disti11ed;in vacuo andfiltered: flthe. residuals :washed with hot Water to dissolve -.-the

lencosesteriretained 'onthe-filtenand the filtrates and washingsvare salted with commonsalt to. pre-.- cipita-te --the-leuco 4 sulphuric ester.

Ezm'mple 18 .7-.-ipa,1\ts ofrN me thylphtha1imidine are addedriiq. Zflpattsofiacetone andr3.1 parts of. methyl ChlOIO-rsfslphon ate are addedto. the-stirred mixture. L'I'he'. mixture is heated to 50 C. for 30 minutespni then cooledlatfiofl. C. .Tothe whitesuspension :so obtainedt lzsparts.of 2echloroanthraquinonesand,. 0-8 @part of .iron powder are .addedand, stirringis. continued.at.20 C. for-2 hours. The. reaction. mixture is poured intoiasolution of 5 parts. 01:80:. diuml r carbonate in 5.100 pants. of. .water. .and .the. suspension is filtered... Theleuco sulphuric ester, isl,. is'olated. by ,salting out from. the -.iiltrlate @a'iter. vacuum. distillation '7i8pa rts:of 'inethylchlorosulphonate are..adde' d' toa'cooled"mixturelof 15:4 parts' of acetopiper-z idide'and 25"parts"ofbenzonitrile. 4-.6 parts of 4:10 dibromoanthanthrone, 2.5 parts of iron powder and 2 parts of tetramethylammonium chloride are then added. The reaction mixture is stirred for 1 hour at 45-50 C. and the yellow suspension so obtained is poured into 10 parts of sodium carbonate dissolved in 200 parts of water. The suspension so obtained is distilled in vacuo. The leuco sulphuric ester is then isolated as described in Example 17.

We claim:

1. A process for the manufacture of leuco sulphuric ester derivatives of vat dyestufi and vat dyestuif intermediate compounds which comprises treating the oxidized form of the vat compound, in the presence of a non-vattable organic amide of a carboxylic acid in which the hydrogen atoms attached to the amide nitrogen atom have been replaced by hydrocarbon radicles and a metal selected from the group consisting of iron, nickel, copper and brass, with a sulphur compound Which will give rise to sulfur trioxid in the mixture and recovering the leuco sulphuric ester derivative of the compound from the reaction mixture.

2. A process for the manufacture of leuco sulphuric ester derivatives of vat dyestuff and vat dyestuif intermediate compounds which comprises treating the oxidized form of the vat compound, in the presence of a, non-vattable organic amide or" a carboxylic acid in which the hydrogen atoms attached to the amide nitrogen atom have been replaced by hydrocarbon radicles and a metal, with sulfur trioxide and recovering the ieuco sulphuric ester derivative of the compound from the reaction mixture, said metal being selected from the group consisting of iron, nickel, copper and brass.

3. A process for the manufacture of leuco sul phuric ester derivatives of vat dyestufi and vat phuric ester derivatives of vat dyestufi and vat dyestufi intermediate compounds which comprises preparing mixture containing sulphur trioxide and a non-vattable'organic amide of a carboxylic acid in which the hydrogen atoms attached to the amide nitrogen atom have been replaced by hydrocarbon radicles, adding to the mixture the vat compound in oxidized form and a metal selected from the group consisting of iron, nickel, copper and brass, stirring the mixture until the compound is converted to the leuco sulphuric ester derivative, adding the reaction mixture to an alkaline solution, and recovering the leuco sulphuric ester derivative from the solution.

5. A process for the manufacture of leuco sulphuric ester derivatives of vat dyestufis which comprises mixing a non-vattable organic amide of a carboxylic acid in which the hydrogen atoms attached to the amide nitrogen have been replaced byhydrocarbon radicles with a sulphur trioxide compound which will give rise to sulphur trioxide in the mixture, adding to the mixture a vat dyestufr in the oxidized form and a metal selected from the group consisting of iron, nickel, copper and brass, stirring the mixture until the dyestufl is converted to the leuco sulphuric ester derivative, pouring the reaction mixture into an 8 aqueous alkaline solution, filtering the resulting suspension, and recovering the leuco sulphuric ester derivative from the filtrate.

6. A process for the manufacture of leuco sulphuric ester derivatives of vat dyestufi and vat dyestuff intermediate compounds which comprises preparing a mixture consisting of a nonvattable organic amide of a carboxylic acid in which the hydrogen atoms attached to the amide nitrogen have been replaced by hydrocarbon radieles, a sulphur trioxide compound which will give-,rise to sulphur trioxide in the mixture, and a diluent, adding to the mixture the vat compound in oxidized form and a metal selected from the group consisting of iron, nickel, copper and brass, stirring the mixture until the vat compound is converted to the leuco sulphuric ester derivative, adding the reaction mixture to an alkaline solution, and recovering the leuco sulphuric ester derivatives from the solution.

SAMUEL COFFEY. r GEORGE WILLIAM DRIVER.

DAVID ALEXANDER WHYTE FAIR/WEATHER, FRANCIS IRVING.

REFERENCES CITED The following-references are of record in the Fairweather et al Feb. 2'7, 1934 

1. A PROCESS FOR THE MANUFACTURE OF LEUCO SULPHURIC ESTER DERIVATIVES OF VAT DYESTUFF AND VAT DYESTUFF INTERMEDIATE COMPOUNDS WHICH COMPRISES TREATING THE OXIDIZED FORM OF THE VAT COMPOUND, IN THE PRESENCE OF A NON-VATTABLE ORGANIC AMIDE OF A CARBOXYLIC ACID IN WHICH THE HYDROGEN ATOMS ATTACHED TO THE AMIDE NITROGEN ATOM HAVE BEEN REPLACED BY HYDROCARBON RADICLES AND A METAL SELECTED FROM THE GROUP CONSISTING OF IRON, NICKEL, COPPER AND BRASS, WITH A SULPHUR COMPOUND WHICH WILL GIVE RISE TO SULFUR TRIOXIDE IN THE MIXTURE AND RECOVERING THE LEUCO SULPHURIC ESTER DERIVATIVE OF THE COMPOUND FROM THE REACTION MIXTURE. 